VI improver, dispersant, and anti-oxidant additive and lubricating oil composition containing same

ABSTRACT

An additive composition prepared by the steps comprising: 
     (A) reacting a styrene-ethylene butylene-styrene block copolymer, having a styrene-ethylene-butylene-styrene molecular weight ratios, respectively, of 1:6:1 to 1:3:1 characterized in that unsaturation in the styrene blocks is equal to or greater than 50 percent and the ethylene butylene block is hydrogenated leaving no more than 10 percent unsaturation, with at least one olefinic carboxylic acid acylating agent to form one or more acylating reaction intermediates characterized by having a carboxylic acid acylating function within their structure, and 
     (B) reacting said reaction intermediate in (A) with an amino-aromatic polyamine compound and a lubricating oil composition containing same are provided.

Background of the Invention

This invention relates to a novel multi-functional lubricant additivewhich is a VI improver, a dispersant and an anti-oxidant additive whenemployed in a lubricating oil composition.

Disclosure Statement

The art contains many disclosures on the use of polymer additives inlubrication oil compositions. Ethylene-propylene copolymers andethylene-alpha olefin non-conjugated diene terpolymers which have beenfurther derivatized to provide bifunctional properties in lubricatingoil compositions illustrate this type of oil additive.

U.S. Pat. No. 3,522,180 discloses a method for the preparation of anethylene-propylene copolymer substrate effective as a viscosity indeximprover for lubricating oils.

U.S. Pat. No. 4,026,809 discloses graph copolymers of a methacrylateester and an ethylene-propylene-alkylidene norbornene terpolymer as aviscosity index improver for lubricating oils.

U.S. Pat. No. 4,089,794 discloses ethylene copolymers derived fromethylene and one or more C₃ to C₂₈ alpha olefin solution grafted with anethylenically-unsaturated carboxylic acid material followed by areaction with a polyfunctional material reactive with carboxyl groups,such as a polyamine, a polyol, or a hydroxyamine which reaction productis useful as a sludge and varnish control additive in lubricating oils.

U.S. Pat. No. 4,137,185 discloses a stabilized imide graft of ethylenecopolymer additive for lubricants.

U.S. Pat. No. 4,146,489 discloses a graph copolymer where the backbonepolymer is an oil-soluble ethylene-propylene copolymer or anethylene-propylene-diene modified terpolymer with a graph monomer ofC-vinylpyridine or N-vinylpyrrolidone to provide a dispersant VIimprover for lubricating oils.

U.S. Pat. No. 4,320,019 discloses a multipurpose lubricating additiveprepared by the reaction of an interpolymer of ethylene and a C₃ -C₈alpha-monoolefin with an olefinic carboxylic acid acylating agent toform an acylating reaction intermediate which is then reacted with anamine.

U.S. Pat. No. 4,340,689 discloses a process for grafting a functionalorganic group onto an ethylene copolymer or an ethylene-propylene-dieneterpolymer.

U.S. Pat. No. 4,357,250 discloses a reaction product of a copolymer andan olefin carboxylic acid via the "ene" reaction followed by a reactionwith a monoamine-polyamine mixture.

U.S. Pat. No. 4,382,007 discloses a dispersant - VI improver prepared byreacting a polyamine-derived dispersant with an oxidizedethylene-propylene polymer or an ethylene-propylene diene terpolymer.

U.S. Pat. No. 4,259,540 and U.S. Pat. No. 4,798,853 disclosestyrene-ethylenebutylene-styrene block copolymers having a styrenerubberratio of from about 0.2 to 0.5 which is useful as a waterproof fillingmaterial for electrical cables.

Elastomerics 120 (10) 30-2 is a treatise on elastomers in general.

European Patent Application, 0173380 discloses block copolymersexhibiting improved elastomeric properties.

The disclosures in the forgoing patents which relate to VI improvers anddispersants for lubricating oils, namely U.S. Pat. Nos. 3,522,180,4,026,809, 4,089,794, 4,137,185, 4,146,489, 4,320,019, 4,340,689,4,357,250, 4,382,007, 4,259,540, 4,427,828, 4,798,853, Elastomerics 120(10) 30-2 and European Patent Application 0173380, are incorporatedherein by reference.

An object of this invention is to provide a novel derivatized graftblock copolymer composition.

Another object of the invention is to provide a multi-functionallubricant additive effective for imparting viscosity index, dispersancyand anti-oxidant properties to a lubricating oil composition.

A further object is to provide a novel lubricating oil compositioncontaining the derivatized graft block copolymer additive of theinvention as well as to provide concentrates of the novel additive ofinvention.

Summary of the Invention

The novel reaction product of the invention comprises a styrene-ethylenebutylene-styrene block copolymer having an S-EB-S molecular weight ratioof 1:6:1 to 1:3:1 on which has been grafted on ethylenically unsaturatedacid anhydride and/or carboxylic acid function which is then furtherderivatized with an amino-aromatic polyamine compound from the groupconsisting of:

(a) an N-arylphenylenediamine represented by the formula: ##STR1## inwhich R¹ is H, -NH-Aryl, -NH-Arylalkyl, a branched or straight chainradical having from 4 to 24 carbon atoms that can be alkyl, alkenyl,alkoxyl, aralkyl alkaryl, hydroxyalkyl or aminoalkyl, R² is NH₂, CH₂-(CH₂)n-NH₂, CH₂ -aryl-NH₂ in which n has a value from 1 to 10, and R3is alkyl, alkenyl, alkoxyl, aralkyl, alkaryl, having from 4 to 24 carbonatoms,

(b) an aminothiazole from the group consisting of aminothiazole,aminobenzothiazole, aminobenzothiadiazole and aminoalkylthiazole,

(c) an aminocarbazole represented by the formula: ##STR2## in which Rand R¹ represent hydrogen or an alkyl or alkenyl, radical having from 1to 14 carbon atoms,

(d) an aminoindole represented by the formula: ##STR3## in which Rrepresents hydrogen or an alkyl radical having from 1 to 14 carbon atoms

(e) an aminopyrrole represented by the formula: ##STR4## in which R is adivalent alkylene radical having 2-6 carbon atoms and RI is hydrogen oran alkyl radical having from 1 to 14 carbon atoms,

(f) an amino-indazolinone represented by the formula: ##STR5## in whichR is hydrogen or an alkyl radical having from 1 to 14 carbon atoms,

(g) an aminomercaptotriazole represented by the formula: ##STR6## (h)and an aminoperimidine represented by the formula: ##STR7## in which Rrepresents hydrogen or an alkyl radical having to 14 carbon atoms.

The novel lubricant of the invention comprises an oil of lubricatingviscosity and an effective amount of the novel reaction product. Thelubricating oil will be characterized by viscosity index improving,dispersancy, and anti-oxidant properties.

Concentrates of the reaction product of the invention are alsocontemplated.

DETAILED DESCRIPTION OF THE INVENTION

The block copolymer substrate employed in the novel additive of theinvention may be prepared from styrene, ethylene and butadiene toproduce a styrene-ethylenebutylenestyrene (S-EB-S) block copolymerhaving an S-EB-S molecular weight ratio of 1:6:1 to 1:3:1.

The polymerization reaction to form the block copolymer substrate may becarried out in the presence of a catalyst in a solvent medium. Thepolymerization solvent may be any suitable inert organic solvent that isliquid under reaction conditions for solution polymerization of olefinswhich is generally conducted in the presence of a Ziegler or aZiegler-Natta type catalyst. Examples of satisfactory hydrocarbonsolvents include straight chain paraffins having from 5-8 carbon atoms,with hexane or cyclohexane being preferred. Aromatic hydrocarbons,preferably aromatic hydrocarbon having a single benzene nucleus, such asbenzene, toluene and the like; and saturated cyclic hydrocarbons havingboiling point ranges approximating those of the straight chainparaffinic hydrocarbons and aromatic hydrocarbons described above, areparticularly suitable. The solvent selected may be a mixture of one ormore of the foregoing hydrocarbons. It is desirable that the solvent befree of substances that will interfere with a Ziegler polymerizationreaction.

The polymeric materials used are substantially linear hydrocarbon blockcopolymers. It is more specifically a hydrogenatedstyrene-ethylenebutylene-styrene (S-EB-S) block copolymer having astyrene-rubber ratio approximately 0.2 to 0.5. The monoalkylenylaromatic hydrocarbon (av. mol. wt. 2,000-115,000) contained in therubber comprises 5-95% of the copolymer. The co-block component, aconjugated diene, viz., butadiene, is the second component of thisrubber (av. mol. wt. 20,000 to 450,000). The material that is ultimatelygenerated has a styrene rubber ratio of approximately 0.2 to 0.5. Uponselective hydrogenation using Raney Nickel or Group VIII metals, such asPt or Pd>50% of the initial unsaturation contained in the monoalkylenylaromatic hydrocarbon remains and <10% of the initial unsaturationcontained in the butadiene remains. This has the advantage of permittingsubsequent melt-mixing of graftable monomer or monomers through anextruder and thermally initiating the free radical graft reaction withor without a free radical thermal initiator.

Di- or tri- or multiblock copolymers are synthesized using anionicinitiators, typically, but not restricted to, Zeigler-Natta catalysismaterials. In those cases where Zeigler-Natta materials are used,transition metal salts are reacted with Group Ia, IIa, or IIIa metalhalides under anhydrous and oxygen-free conditions in a variety of inertsolvents. This method is very well known and described in the art. Otheranionic catalysis are known including using Group Ia metals directly.This method is also well known and thereto described in the art.

Polymeric materials containing hydrogenated block segments ofhydrogenated styrene-ethylene-butylene-styrene are availablecommercially and are sold under the tradename `Kraton`.

An ethylenically unsaturated material containing pendant acid anhydrideand carboxylic acid groups is grafted onto the prescribed polymerbackbone. These materials which are attached to the polymer contain atleast one ethylenic bond and at least one, preferably two, carboxylicacid or its anhydride groups or a polar group which is convertible intoa carboxyl group by oxidation or hydrolysis. Maleic anhydride or aderivative thereof is preferred. It grafts onto the block copolymer togive two carboxylic acid functionalities. Examples of additionalunsaturated carboxylic materials include chlormaleic anhydride, itaconicanhydride, or the corresponding dicarboxylic acids, such as maleic acid,fumaric acid and their monoesters.

The ethylenically unsaturated carboxylic acid material may be graftedonto the block copolymer backbone in a number of ways. It may be graftedonto the backbone by a thermal process known as the "ene" process or bygrafting in solution or in solid form using a radical initiator. Thefree-radical induced grafting of ethylenically unsaturated carboxylicacid materials in solvents, such as benzene is a preferred method. It iscarried out at an elevated temperature in the range of about 100° to250° C., preferably 120° to 190° C. and more preferable at 150° to 180°C., e.g. above 160° C., in a solvent, preferably a mineral lubricatingoil solution containing, e.g. 1 to 50, preferably 5 to 30 wt.%, based onthe initial total oil solution, of the block copolymer and preferablyunder an inert environment.

The free-radical initiators which may be used are peroxides,hydroperoxides, and azo compounds and preferably those which have aboiling point greater than about 100° C. and decompose thermally withinthe grafting temperature range to provide free radicals. Representativeof these free-radical initiators are azobutyronitrile and-2,5-dimethyl-hex-3-yne-2, 5-bis-tertiary-butyl peroxide. The initiatoris used in an amount of between about 0.005% and about 1% by weightbased on the weight of the reaction mixture solution. The grafting ispreferably carried out in an inert atmosphere, such as under nitrogenblanketing. The resulting graft block copolymer intermediate ischaracterized by having carboxylic acid acylating functions within itsstructure.

In the solid or melt process for forming a graft block copolymer, theunsaturated carboxylic acid with the optional use of a radical initiatoris grafted on molten rubber using rubber masticating or shearingequipment. The temperature of the molten material in this process mayrange from about 150°-400° C. using a twin-screw extruder. Thetemperature in the barrel in such that the free radical initiator isactivated and maleic anhydride grafts exclusively to the EP portion ofthe terpolymer without decomposition of polymeric material.

Polymeric materials containing hydrogenated blocks ofstyrene-ethylene-butylene-styrene with grafted succinic anhydride areavailable commercially and are sold under the tradename `Kraton(R)FG1901X`.

The block copolymer intermediate possessing acid anhydride andcarboxylic acid acylating functions is reacted with an amino-aromaticpolyamine compound from the group consisting of:

(a) an N-arylphenylenediamine represented by the formula: ##STR8## inwhich R¹ is H, -NH-Aryl, -NH-Arylkyl, a branched or straight chainradical having from 4 to 24 carbon atoms that can be alkyl, alkenyl,alkoxyl, aralkyl alkaryl, hydroxyalkyl or aminoalkyl,

R² is NH₂, CH₂ -(CH₂)_(n) -NH₂, CH₂ -aryl-NH₂ in which n has a valuefrom 1 to 10, and R₃ is alkyl, alkenyl, alkoxyl, aralkyl, alkaryl,having from 4 to 24 carbon atoms,

(b) an aminothiazole from the group consisting ofaminoaminobenzothiazole, aminobenzothiazole, aminobenzothiadiazole andaminoalkylthiazole,

(c) an aminocarbazole represented by the formula: ##STR9## in which Rand R¹ represent hydrogen or an alkyl or alkenyl, radical having from 1to 14 carbon atoms,

(d) an aminoindole represented by the formula: ##STR10## in which Rrepresents hydrogen or an alkyl radical having from 1 to 14 carbon atoms

(e) an aminopyrrole represented by the formula: ##STR11## in which R isa divalent alkylene radical having 2-6 carbon atoms and R¹ hydrogen oran alkyl radical having from 1 to 14 carbon atoms, ##STR12## in which Ris hydrogen or an alkyl radical having from 1 to 14 carbon atoms

(g) an aminomercaptotriazole represented by the formula: ##STR13## (h)an aminoperimidine represented by the formula: ##STR14## in which Rrepresents hydrogen or an alkyl or alkoxyl radical having from 1 to 14carbon atoms.

Particularly preferred N-arylphenylenediamines are theN-phenylphenylenediamines, for example, N-phenyl-1,-4-phenylenediamine,N-phenyl-1,3-phenylenediamine, and N-phenyl-1,2-phenylenediamine.

The process for preparing this multifunctional VI improver involvescharging diluent oil and solid grafted rubber Kraton(R) to the reactionflask and dissolving the rubber in oil at 160° C. under a nitrogenblanket. An amino-aromatic polyamine compound, e.g.N-phenyl-p-phenylenediamine (NPPDA) is then charged as a neat granularsolid or as a 10-20% solution in an oil soluble solvent, such ascommercial alkyl or alkylaryl polyethylene or propylene glycol. Theimidization step of reacting NPPDA with the polymer-bound succinicanhydride groups is carried out over several hours at the aforementionedtemperature under nitrogen. On completion of the reaction the materialis cooled to 100.C and screen filtered through a 100 mesh filter and theproduct isolated. This VI improver may be added to lubricating oils toimpart viscosity index improvement, dispersancy, and thermal-oxidativestability.

The following examples illustrate the preparation of the novel reactionproduct additive of the invention.

Example I

60 grams of a solid maleic anhydride graft styreneethylenebutylene-styrene block copolymer (S-EB-S Kraton R rubber) having averagemolecular weights for S-EB-S of 7,500-37,500-7,500, respectively, onwhich is grafted 0.2 to 4.6 weight percent of maleic anhydride isdissolved in 485 grams of solvent neutral oil at 160 C with mechanicalstirring while the mixture is maintained under a nitrogen blanket. Therubber polymer is dissolved and mixing is continued for an additionalhour at 160° C.

1.85 grams of neat N-phenyl-1,4-phenylenediamine is added to the oilsolution of the polymer and a reaction is effected over 4 hours at 160°C. under nitrogen. The reaction mixture containing the derivatized graftblock copolymer is then cooled and filtered.

Example II

70 grams of solid maleic anhydride graft styreneethylenebutylene-styrene block copolymer (S-EB-S Kraton R rubber of Examples I)is dissolved in 513 grams of solvent neutral oil at 160° C. withmechanical stirring while the mixture is maintained under a nitrogenblanket. The polymer is dissolved and mixing is continued for anadditional 3 hours at 160° C.

1.1 grams of neat N-phenyl-1,4-phenylenediamine is added to the oilsolution of the polymer and a reaction is effected over 4 hours at 160°C. under nitrogen. The reaction mixture containing the derivatized graftblock copolymer is cooled and then filtered through a 100 mesh screen.

Example III

70 grams of a solid maleic anhydride graft styreneethylenebutylene-styrene block copolymer (S-EB-S Kraton R rubber of Example I)is dissolved in 513 grams of solvent neutral oil at 160° C. withmechanical stirring while the mixture is maintained under a nitrogenblanket. The polymer is dissolved and mixing is continued for oneadditional hours at 160° C.

1.0 grams of N-phenyl-1,4-phenylenediamine dissolved in 5 grams ofpolypropylene glycol of 400 molecular weight is added to the oilsolution of the polymer and a reaction is effected over two hours at160° C. under nitrogen. The reaction mixture containing the derivatizedgraft block copolymer is cooled and filtered through a 100 mesh screen.

The novel graft and derivatized block copolymer of the invention isuseful as an additive for lubricating oils. These products aremulti-functional additives for lubricants being effective to providedispersancy, viscosity index improvement and anti-oxidant properties tolubricating oils. They can be employed in a variety of oils oflubricating viscosity including natural and synthetic lubricating oilsand mixtures thereof. The novel additives can be employed in crankcaselubricating oils for spark-ignited and compression-ignited internalcombustion engines. The compositions can also be used in gas engines, orturbines, automatic transmission fluids, gear lubricants, metal-workinglubricants, hydraulic fluids and other lubricating oil and greasecompositions. Their use in motor fuel compositions is also contemplated.

The base oil may be a natural oil including liquid petroleum oils andsolvent-treated or acid-treated mineral lubricating oils of theparaffinic, naphthenic and mixed paraffinic-naphthenic types.

In general, the lubricating oil composition of the invention willcontain the novel reaction product in a concentration ranging from about0.1 to 30 weight percent. A preferred concentration range for theadditive is from about 0.1 to 15 weight percent based on the totalweight of the oil composition.

Oil concentrates of the additives may contain from about 1 to 20 weightpercent of the additive reaction product in a carrier or diluent oil oflubricating oil viscosity. The novel reaction product of the inventionmay be employed in lubricant compositions together with conventionallubricant additives. Such additives may include additional dispersants,detergents, anti-oxidants, pour point depressants, anti-wear agents andthe like. The novel additive reaction product of the invention is testedfor its effectiveness as a dispersant and as an anti-oxidant in aformulated lubricating oil composition. The base lubricating oil used inthe dispersancy test is a typical formulated lubricating oil withrepresentative values illustrated in Table I.

                  TABLE I                                                         ______________________________________                                                           Parts By                                                                      Wgt.                                                       ______________________________________                                        Component                                                                     Solvent neutral oil A                                                                              75.25                                                    Solvent neutral oil B                                                                              21.64                                                    Zinc Dialkyldithioposphate                                                                         1.22                                                     4.4'dinonyldiphenylamine                                                                           .39                                                      Overbased magnesium sulfonate                                                                      1.50                                                     Silicone anifoamant  150 PPM                                                  Product              10                                                       Analyses                                                                      Viscosity Kin 40C CS 30.4                                                     Viscosity Kin 100C CS                                                                              5.33                                                     Pour Point, F.       +10                                                      Ash Sulfated, % D874 0.88                                                     Phosphorus, % X-Ray  0.12                                                     Sulfur, % X-Ray Total                                                                              0.32                                                     Zinc, % X-Ray        0.13                                                     ______________________________________                                    

Oil A has a sp. gr. 60/60° F. of 0.858-0.868; Vis 100.F. 123-133; pourpoint 0° F. Oil B is sp. gr. 60/60° F. of 0.871-0.887; Vis. 100° F.325-350; Pour Point +10° F. Zinc salt is a salt of mixedalcohols-ispropanol and P₂ S₂ product as described in U.S. Pat. No.3,292,181. The overbased magnesium sulfonate has a TBN of 395 and is asalt of branched C₂₀ -C₄₀ monoalkybenzene sulfuric acid (MW 530-540)together with about 10% magnesium carbonate, 14% magnesium hydroxide and4% magnesium sulfate.

The dispersant properties of the additive-containing oil are determinedin the Bench VC Dispersancy Test (BVCT). Dispersancy of a lubricatingoil is determined relative to three reference results from threestandard blends tested along with the unknown. The test additives areblended into a formulated oil containing no dispersant. The additivereaction product is employed in the oil at a concentration of 1.20weight percent polymer solution. The numerical value of the test resultsdecreases with an increase in effectiveness.

                  TABLE II                                                        ______________________________________                                        BENCH VC DISPERSANCY TEST                                                     Run      Additive             Result                                          ______________________________________                                        1.       Example 1            28                                              2.       Example 2            31                                              3.       Maleic Anhydride Graft                                                                             93                                              4.       Commercial N-vinylprrolidone-                                                                      29                                                       grafted dispersant olefin copolymer                                  ______________________________________                                         (1) Maleic anhydride grafted styreneethylene-butylene-styrene block           copolymer (Kraton (R)).                                                  

The anti-oxidant properties of the novel reaction product in alubricating oil is determined in the Bench Oxidation Test. In this test,1.5 weight percent of the additive reaction product is blended intosolvent neutral oil (S.U.S. at 100° F. of 130). The mixture iscontinuously stirred while being heated accompanied by bubbling withair. Samples are withdrawn periodically for analysis by DifferentialInfrared Absorption (DIR) to observe changes in the intensity of thecarboxyl vibration band at 1710 cm-1. A low carboxyl vibration bandintensity indicates higher thermal-oxidative stability of the sample.

                  TABLE III                                                       ______________________________________                                        BENCH OXIDATION TEST                                                          Run      Additive             Result                                          ______________________________________                                        1.       Example I            0                                               2.       Example II           0                                               3.       Commercial N-vinylprrolidone-                                                                      15                                                       grafted dispersant olefin                                                     Copolymer (DOCP)                                                     ______________________________________                                    

The test results for Examples I and II demonstrate substantialimprovements in anti-oxidant properties due to incorporation of thenovel reaction product of the invention in an oil composition ascompared to the results obtained using a known dispersant VI improverand the underivatized graft block copolymer rubber.

What is claimed is:
 1. A lubricating oil additive composition preparedby the steps comprising:(A) reacting a styrene-ethylenebutylene-styreneblock copolymer, having styrene-ethylenebutylene-styrene molecularweight ratios, respectively, of 1:6:1 to 1:3:1 characterized in thatunsaturation in the styrene blocks is equal to or greater than 50percent and and the ethylene butylene block is hydrogenated leaving nomore than 10 percent unsaturation, with at least one olefinic carboxylicacid acylating material to form one or more acylating reactionintermediates characterized by having a carboxylic acid acylatingfunction within their structure, and (B) reacting said reactionintermediate in (A) with an amino-aromatic polyamine compound selectedfrom the group consisting of:(a) an N-arylphenylenediamine representedby the formula: ##STR15## in which R¹ is hydrogen, -NH-aryl,NH-arylalkyl, a branched or straight chain radical having from 4 to 24carbon atoms that can be alkyl, alkenyl, alkoxyl, aralkyl, alkaryl,hydroxyalkyl or aminoalkyl, R² is NH₂, CH₂ -(CH₂)_(n) --NH₂, CH₂-aryl-NH₂ in which n has a value from 1 to 10, and R³ is alkyl, alkenyl,alkoxyl, aralkyl, alkaryl having 4 to 24 carbon atoms, (b) anaminocarbazole represented by the formula: ##STR16## in which R and R¹represent hydrogen or an alkyl or alkenyl radical having from 1 to 14carbon atoms, (c) an aminoindole represented by the formula: ##STR17##in which R represents hydrogen or an alkyl radical having from 1 to 14carbon atoms, (d) an aminopyrrole represented by the formula: ##STR18##in which R is a divalent alkylene radical having 2 to 6 carbon atoms andR¹ hydrogen or an alkyl radical having from 1 to 14 carbon atoms, (e) anamino-indazolinone represented by the formula: ##STR19## in which R ishydrogen or an alkyl radical having from 1 to 14 carbon atoms, (f) anaminomercaptotriazole represented by the formula: ##STR20## and (g) anaminoperimidine represented by the formula: ##STR21## in which Rrepresents hydrogen or an alkyl radical having from 1 to 14 carbonatoms.
 2. A lubricating oil additive composition according to claim 1 inwhich said copolymer has an average molecular weight from about 25,000to 250,000.
 3. A lubricating oil additive composition according to claim1 in which said copolymer has an average molecular weight from about50,000 to 150,000.
 4. A lubricating oil additive composition accordingto claim 1 in which said olefinic carboxylic acid acylating material ismaleic anhydride.
 5. A lubricating oil additive composition according toclaim 1 in which said olefinic carboxylic acid acylating material isitaconic anhydride.
 6. A lubricating oil composition comprising a majoramount of an oil of lubricating viscosity and a minor amount effectiveto impart viscosity index, dispersance, and anti-oxidant properties tosaid oil of an additive composition prepared by the steps comprising:(A)reacting a styrene-ethylenebutylene-styrene block copolymer, havingstyrene-ethylenebutylene-styrene molecular weight ratios, respectively,of 1:6:1 to 1:3:1 characterized in that unsaturation in the styreneblocks is equal to or greater than 50 percent and and theethylenebutylene block is hydrogenated leaving no more than 10 percentunsaturation, with at least one olefinic carboxylic acid acylatingmaterial to form one or more acylating reaction intermediatescharacterized by having a carboxylic acid acylating function withintheir structure, and (B) reacting said reaction intermediate in (A) withan amino-aromatic polyamine compound selected from the group consistingof:(a) an N-arylphenylenediamine represented by the formula: ##STR22##in which R¹ is hydrogen, -NH-aryl, NH-arylalkyl, a branched or straightchain radical having from 4 to 24 carbon atoms that can be alkyl,aralkyl, alkaryl, hydroxyalkyl or aminoalkyl, R² is NH₂, CH₂ -(CH₂)_(n)-NH₂, CH₂ -aryl-NH₂ in which n has a value from 1 to 10, and R³ isalkyl, aralkyl, alkaryl of from 4 to 24 carbon atoms, (b) anaminocarbazole represented by the formula: ##STR23## in which R and R¹represent hydrogen or an alkyl or alkenyl radical having from 1 to 14carbon atoms, (c) an aminoindole represented by the formula: ##STR24##in which R represents hydrogen or an alkyl radical having from 1 to 14carbon atoms, (d) an aminopyrrole represented by the formula: ##STR25##in which R is a divalent alkylene radical having 2 to 6 carbon atoms andR¹ hydrogen or an alkyl radical having from 1 to 14 carbon atoms, (e) anamino-indazolinone represented by the formula: ##STR26## in which R ishydrogen or an alkyl radical having from 1 to 14 carbon atoms, (f) anaminomercaptotriazole represented by the formula: ##STR27## and (g) anaminoperimidine represented by the formula: ##STR28## in which Rrepresents hydrogen or an alkyl radical having from 1 14 carbon atoms.7. A lubricating oil composition according to claim 6 containing fromabout 0.1 to 15 weight percent of said additive based on the totalweight of the oil composition.
 8. A lubricating oil compositionaccording to claim 6 containing from about 1 to 7.5 weight percent ofsaid additive based on the total weight of the oil composition.
 9. Aconcentrate for a lubricating oil comprising a diluent oil of lubricantviscosity and from about 1 to 20 weight percent of the lubricating oiladditive composition of claim 1 based on the total weight of theconcentrate.
 10. An additive composition prepared by the stepscomprising:(A) reacting a styrene-ethylenebutylene-styrene blockcopolymer, having styrene-ethylenebutylene-styrene molecular weightratios, respectively, of 1:6:1 to 1:3:1 characterized in thatunsaturation in the styrene blocks is equal to or greater than 50percent and and the ethylenebutylene block is hydrogenated leaving nomore than 10 percent unsaturation, with at least one olefinic carboxylicacid acylating material to form one or more acylating reactionintermediates characterized by having a carboxylic acid acylatingfunction within their structure, and (B) reacting said reactionintermediate in (A) with an amino-aromatic polyamine compound in whichsaid compound is an N-aryl or N-alkyl substituted phenylenediamine. 11.An additive composition according to claim 10 in which said compound isan N-phenylphenylenediamine.
 12. An additive composition according toclaim 10 in which said compound is N-phenyl-1,4-phenylenediamine.
 13. Anadditive composition according to claim 10 in which said compound isN-phenyl-1,3-phenylenediamine.
 14. A lubricating oil compositionaccording to claim 6 in which N-arylphenylenediamine isN-phenyl-1,4-phenylenediamine.